Processed ground-motion records from induced earthquakes for use in engineering applications

Abstract

We compile and process an electronic database of ground motions recorded on accelerometers and broadband seismographic instruments for induced earthquakes of M ≥ 4 at distances <50 km in central and eastern North America. Most of the data are from Oklahoma, with some records from Alberta. Our focus is on the subset of available records that are of most interest for engineering analyses aimed at evaluation of the potential hazards from induced events, which is a pressing issue in western Canada and other regions experiencing induced seismicity. We considered all records to 50 km for events of M ≥ 4.5. For events of M 4 to 4.5, we select records at close distance (<10 km), having good signal strength (PGA > ∼3%g), to allow high-quality time histories to be obtained. These records have strong signal-to-noise ratio, making them suitable for engineering applications, such as dynamic analysis, after proper scaling. The selected records are windowed, filtered, and instrument-corrected to compile a set of records having acceptable acceleration, velocity, and displacement time histories. The records and their response spectra are provided as an electronic supplement at http://www.seismotoolbox.ca/IS_Strong_Motions/ . We note that the record set is not suitable as a response spectra database for development of ground-motion prediction equations, because for M < 4.5 the record selection is biased to records with higher amplitudes. Rather, the intended use of the records is as seed records, which can be readily scaled in the time domain to approximately represent induced-event target scenarios for engineering applications.